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Organization of club moss gametophytes and juvenile sporophyte populations in pine forests

100%

Rimgaile-Voicik R. , Naujalis J. R. , Voicikas A.

Polish Journal of Ecology

2015

tom 63

nr 4

Initial populations of club mosses were investigated in pine forests of southern Lithuania (ass. Cladonio-Pinetum and Vaccinio vitis-idaeae-Pinetum). Results show that populations of lycophyta gametophytes in some forest sites can be abundant (up to 500 individuals in a square meter). All juvenile populations were found in localities where recorded tree canopy cover was 30% or less. Localization of subterranean gametophyte populations was determined by juvenile club mosses. We mapped locations of all Lycopodium L. and Diphasiastrum Holub. juvenile sporophytes and gametophytes that occurred within three randomly selected and excavated 0.25 m² sample plots at four pine forest sites in different localities in southern Lithuania. The developmental stage of each individual was recorded. Eight out of twelve soil samples from four research localities contained subterranean gametophytes. In total 277 gametophytes and 124 juvenile sporophytes were recorded. The developmental stage and size of the gametophytes varied. Gametophytes were divided into six categories on the basis of external features. Spatial distribution of gametophytes and juvenile sporophytes were evaluated using a nearest neighbor analysis (NNA). Our results suggest that initial populations of gametophytes in pine forests are multi-aged and display a relatively stable degree of spatial aggregation. Greater aggregation occurred among juvenile sporophytes.

A new and fast method to obtain in vitro cultures of Huperzia selago (Huperziaceae) sporophytes, a club moss which is a source of huperzine A

80%

Szypula W. J. , Mistrzak P. , Olszowska O.

Acta Societatis Botanicorum Poloniae

2013

tom 82

nr 4

This study presents a protocol for a fast and effective in vitro axenic culture of Huperzia selago (Huperziaceae Rothm.) sporophytes, a club moss which is a source of huperzine A, an alkaloid of a considerable therapeutic potential extensively investigated for its uses as treatment for some neurodegenerative diseases. The proposed procedure allowed approximately tenfold shortening of the species developmental stages with the omission of the gametophyte stage while the sporophyte mass could be increased tenfold within a 6-month period. The cultures were established using vegetative propagules (bulbils) procured from sporophytes growing in the wild without degrading the habitats of this endangered plant species. Explants underwent surface and internal disinfection to eliminate the epiphytic and endophytic bacteria and fungi. In in vitro cultures, the optimum results were achieved using Moore (Mr) medium without growth regulators or supplemented with 0.015 mg/l IBA and 0.3 mg/l kinetin. These media ensured both viability of the propagules and their further development. The biomass growth index for H. selago sporophytes grown from propagules, determined at 3 months of culture (1 passage) on Mr medium with IBA and kinetin was 650%. At 6 months, the biomass growth index increased to 1114%. Vigorous growth of adventitious roots, especially on Mr medium with the addition of 0.25 mg/l NAA, and callus formation on shoot apices were observed. At 6 months of culture, some sporophytes obtained from the bulbils were used as the initiating material for shoot subcultures, which developed best on Mr medium with IBA and kinetin.

Influence of site conditions on the diversity of endophytic fungi of fir clubmoss Huperzia selago (L.) Bernh. ex. Schrank et Mart

70%

Budziszewska J. , Szypula W.

Polish Journal of Ecology

2010

tom 58

nr 4

The aim of the study was to assess the influence of environmental conditions on the composition of endophytic assemblages associated with fir clubmoss, Huperzia selago (L.) Bernh. ex Schrank et Mart. This clubmoss is a cosmopolitan species widely spread in Eurasia and North America, and its gametophytes and sporophytes are colonised by endophytic fungi. Plants for this study were collected in October 2004 and between April and October 2007 from seven European sites, differing in altitude, average annual precipitation, temperature and plant community. Endophytes were isolated on PDA medium (4% potato-dextrose agar) and identified through morphological observations. Different ecological indices were calculated for each site like colonization factor, Fisher’s alpha, Shannon’s diversity, Morista-Horn and Jaccard’s indices. Our results prove that altitude positively correlates with species diversity (Fisher’s alpha) and species richness (number of species). Moreover, the similarity assessed from Jaccard’s (0.66 for Larici-Piceetum sites) and Morista-Horn indices (0.77 for Juncetea trifidi sites) suggest the influence of plant community on fungal endophyte composition.